Análisis de residuos de contaminantes orgánicos en alimentos por técnicas cromatográficas.
Food contamination by chemical substances is a Public Health problem, all over the world. The cause could be as a consequence of environmental contamination that food chains could rise through air, water and soil as it occurs in the case of metals, PCBs, dioxins, etc. Contribute also the deliberate (intentionate) use of several chemical products, as pesticides, drugs or different substances administrated to animals and other agrochemical products. Few additives used in food as manufacturing and processing that can also contribute to add contaminants.
In order to control food safety, several environmental and quality agencies take care of the compliance of legislation, through the application of adequate analytical methods to determinate in quick and efficient of contaminants in food by using multirresidue methodologies and carrying out sampling and food controls in food in commercializing phase.
To analyze organic contaminants in food is a hard task which implies different and many disciplines as chemistry, biochemistry and microbiology. It is not a easy task, and many contaminants could be enumerated. They are presented at very low concentrations, complex matrices and among compounds of natural food. However, to analyze samples with complex matrices and with analytes at very low concentrations makes necessary to apply separation techniques in analytical procedures with the double objective of improve selectivity and sensibility. In this context, different separation analytical techniques, being of special relevance chromatographic techniques has been developed, because of the importance in actual analytical chemistry.
The objective of this thesis is the determination of residues of two organic contaminants, pesticides and veterinary drugs, by using different chromatographic techniques to evaluate the degree of food safety.
For this, partial objectives have to be approached:
1.-Pesticide and veterinary drugs residues extraction by using classical extraction procedures, as solid phase extraction and other more innovatives, as stir bar sorptive extraction and pressurized solvent extraction.
2.-Pesticide analysis by liquid cromatography-mass spectrometry previous the use of the extraction methods like solid phase extraction and stir bar sorptive extraction.
3.-Comparison of on-line preconcentration techniques, for the pesticide analysis in order to reach adequated limits of detection for its determination in fruits and vegetables by capillary electrophoresis.
4.-Study the use of mass spectrometry as a determination technique coupled to capillary electrophoresis using different mass analyzers, capillary electrophoresis-single quadrupole and capillary electrophoresis-ion trap to carry out these techniques in pesticide and veterinary drugs residue detection.
5.-Apply the selected analytical procedures to different vegetable products as grapes, strawberry, tomato, lettuce, peaches and nectarines, as well as to animal food such as fish, chicken and pork.
It was concluded that the quantitative and simultaneous determination in food samples from Valencian Community, through solid phase extraction, sitr-bar sorptive extraction or pressurized liquid extraction and by capillary electrophoresis with diode array or mass spectrometry detection, make known the utility of capillary electrophoresis for pesticide residues determination in complex fruit and vegetable matrices as grape, lettuce, tomato, strawberry, peach and nectarines and veterinary drug residues in animal origin food as fish and chicken and pork meat.
The presence of organic contaminants residues in food, although in few samples percentage and often at a low concentrations, makes necessary to develop and optimize methods in order to ensure that its correct determination allows an appropriate food safety.
Advisor:Font Pérez, Guillermina; Picó García, Yolanda
School:Universitat de València
Source Type:Master's Thesis
Keywords:medicina preventiva i salut pública bromatologia toxicologia legal
Date of Publication:03/07/2008